As a main memory of a processor, conventionally, a DRAM (Dynamic Random Access Memory) has been used. However, the DRAM requires to be refreshed periodically, and hence power consumption increases. Therefore, there is a proposed technique to use a large-capacity non-volatile memory as the main memory, instead of the DRAM.
However, it is not so rare for the non-volatile memory to have a lower write speed and lower rewrite durability than the DRAM.